NSX upgrade prechecks error Authentication failed on fileserver sftp..nfs-mount/backup..error_code=29115

Products

• VMware SDDC Manager

Issue/Introduction

• NSX upgrade prechecks/upgrade from SDDC manager fails with error "Authentication failed on fileserver sftp://<SDDC Manager FQDN>:22/nfs/vmware/vcf/nfs-mount/backup., httpStatus=BAD_REQUEST, error_code=29115"
• Taking a backup from NSX manager directly fails with the same error.
• In /var/log/vmware/vcf/lcm-debug.log, you may see below snippet:
  • data = struct => {error_message=Authentication failed on fileserver sftp://<SDDC Manager FQDN>:22/nfs/vmware/vcf/nfs-mount/backup/xxxxxxxxx, httpStatus=BAD_REQUEST, error_code=29115, module_name=backup-restore},
    errorType = INVALID_REQUEST
}

Environment

VCF 5.x

Cause

This issue occur due to the sddc backup user account being locked.

Resolution

1. Connect to sddc manager via ssh as a vcf user
2. Switch to root su - command.
3. Run lookup_passwords and fetch the stored backup user password
4. Run faillock --user backup --reset to unlock the backup user account.
5. Run passwd backup command to set the backup user's password to the value returned by the Step #3 command